Just got the Topeak HRM and speed Cadence sensor installed on the bike. Connected first time to both without an issue. (Though the speed sensor didn't work till I installed the battery)
I have an Android HTC One with OS 4.3
Tested with Runtastic Map my Ride and Topeaks Panobike App.
I believe it connects to Strava too but I have the unpaid version.
Will report after a few rides but wanted to let people know about the Android compatibility.